WD MyStudio - Invalid Node Structure

[MacUserSince87]

I've been running a WB 1TB MyStudio FW800 drive as for Time Machine back-up for a year or so. I had it set up as two partitions. A few weeks ago one the partition used for Time Machine stopped working. A verify revealed an Invalid Node Structure error.

I reformatted the disk, overwriting with zeros, as a single partition and it checked out OK and ran OK for a couple weeks. But now I'm getting the same Invalid Node Structure error.

Is it time to bite the bullet and replace it?

 

[MacUserSince87]

Follow-up

A follow-up for the benefit of other WD owners:

Checking the WD support site:
http://support.wdc.com/product/download.asp?lang=en

I discovered by entering my HD serial number that it still qualified for full-warranty replacement. The 1TB FW 800 drive I have is no longer made so WD is sending a newer model to replace it. Because I had registered my drive my contact info was on file and the RMA procedure was quite simple. WD will ship an immediate replacement if credit card info. is supplied. No charge is made if the defective drive is returned in 30 days.

After posting my initial message about the directory node error the drive crapped out all together and wouldn't even power up. But today when I tried it again it worked and I've been able to reformat it and wipe the data by overwriting with zeros. When first trying to reformat it failed with an "can't ummount disk" message, but after repeated tries I was able to do a simple directory erase reformat, then reformatted it again with zero overwrite.

So the moral of the story is that if at first you don't succeed, keep trying.

 

[MacUserSince87]

Yet another twist to the story. I received the replacement drive from WD but found it would mount using USB and FW400 but not when connected via FW800 cable. I reinstalled firmware and tried a different cable to no avail.

I called WD support again, reaching someone in India who wasn't much help. She transferred it up an level and that person agreed to send another drive.

Shortly after that while searching for a solution is came across a reference to pple Tech Note: http://support.apple.com/kb/HT1317 which discusses FW problems.

I discovered that the FW port has a fuse that can trip when a powered source like an external drive is attached. Resetting the fuse required shutting down the machine, removing all FW devices and giving it a 5 min. time out. After rebooting with no FW devices connected, powering down, connecting the drive turning its power on and rebooting the iMac recognized and mounted the drive.

The second replacement drive arrived yesterday but it was damaged in shipment due to poor internal packing in the box. So I'll be keeping the first replacement and sending that one back with the supplied return label.

I spoke to a WD rep and relayed the information about resetting the FW buss and hopefully they will add it to the support information database.